useCallback in React: Purpose & Optimization

In React, useCallback is a custom hook used to optimize performance. Its purpose is to cache a function in order to avoid recreating it every time it is rendered. This ensures that the component only re-renders when its dependencies change, instead of creating a new function instance every time.

Using useCallback can improve performance, especially when passing callback functions as props to child components. By caching the callback functions, you can avoid creating new callback function instances on every render, thus reducing unnecessary re-renders.

In conclusion, useCallback can help optimize performance by avoiding unnecessary re-renders, especially when dealing with callback functions.